A Problem with Simplify

*To*: mathgroup at smc.vnet.net*Subject*: [mg87419] A Problem with Simplify*From*: "Kevin J. McCann" <Kevin.McCann at umbc.edu>*Date*: Thu, 10 Apr 2008 02:12:11 -0400 (EDT)*Organization*: University System of Maryland

I have the following rather simple integral of two sines, which should evaluate to zero if m is not equal to n and to L/2 if they are the same. The following is just fine Imn = Simplify[Integrate[ Sin[(m*Pi*x)/L]* Sin[(n*Pi*x)/L], {x, 0, L}]] However, if I specify that m and n are integers, I only get the "general" solution of zero, i.e. when m and n are not equal. Imn = Simplify[Integrate[ Sin[(m*Pi*x)/L]* Sin[(n*Pi*x)/L], {x, 0, L}], Element[m, Integers] && Element[n, Integers]] The workaround is obvious in this case, but shouldn't mma give multiple answers? Perhaps something similar to what it already does with Integrate? Kevin -- Kevin J. McCann Research Associate Professor JCET/Physics Physics Building University of Maryland, Baltimore County 1000 Hilltop Circle Baltimore, MD 21250

**Follow-Ups**:**Re: A Problem with Simplify***From:*Andrzej Kozlowski <akoz@mimuw.edu.pl>